Abstract: The hydrogenation reaction of CO and CO2 to synthesize methanol is a multiple reaction system. The distributions of concentrations are described by second order ordinary differential equations.The Eighenfunction method is used to solve the differential equations in terms of the characteristic of the system. In this paper,the kinetic equations are hyperbolic type and the catalyst grain of the methanol synthesis are regarded to be isothermal.The numerical calculations of efficiency factors are coincided with the experiment results.